This invention relates to the use of ozone in the treatment of dental caries.
The great destructive disease of teeth is dental caries which may be defined as the acid dissolution of enamel, dentine or cementum as a consequence of the metabolism of micro-organisms living within deposits on the teeth known as plaque. Dental caries are believed to be associated with specific micro-organisms, the principal ones being Streptococcus Mutans, Lactobacilli, Actinomyces Visosus Serovar 2, Actinomyces Naeslundii and xe2x80x9cIntermediatexe2x80x9d Actinomyces, other Streptococci and yeasts. These are acid producing micro-organisms which produce acids such as acetic and lactic acids from the dietary carbohydrates. The micro-organisms associated with dental caries are unique and are ecologically very different from those associated with, for example, infected root canals.
Dental caries is currently managed by one or more of the following:
(i) preventive treatment by, for example, dietary and oral hygiene measures and may include the topical application of chemotherapeutic agents;
(ii) the removal of dentine exhibiting the signs of active caries;
(iii) the protection of any newly exposed non-carious dentine with restorative material.
Measures aimed at the prevention or the arrest of dental caries are mainly based on the elimination of dental plaque from the surfaces of roots and the institution of dietary controls to reduce the frequency and quantity of readily fermentable carbohydrate ingestion. The mechanical removal of plaque has been a major platform for the prevention of dental caries for some time. However, this poses special problems in the case of primary root caries due to access problems. Because dentine has a Knoop hardness of 68 in contrast to enamel at 11, the mechanical removal of plaque from its surface inevitably results in some loss of tissue also. Toothbrush abrasion is now a very common phenomenon and invariably leads to the loss of root dentine from the facial aspects of teeth. Consequently, the traditional methods of plaque control in the prevention of dental caries create further problems even when access permits it to be used effectively.
Conventional caries removal and cavity preparation entail the use of high and low speed handpieces. However, disadvantages of this system include the perception that drilling is unpleasant for patients and local anaesthetic is frequently required. Furthermore, handpieces are expensive to purchase and maintain and their use may lead to the removal of softened but uninfected dentine resulting in the excessive loss of tooth tissue.
Where restoration is required, all materials used to restore carious lesions have their limitations. For example, gold and ceramic are expensive and present a technical challenge for the practitioner. While amalgam is a durable, predictable material, it has poor aesthetic qualities, is potentially toxic and may cause allergic reactions in some people.
It is an object of the invention to alleviate the disadvantages of the prior art.
It has now unexpectedly been found that ozone can penetrate carious tissue and can therefore be used in the treatment of dental caries.
According to the present invention there is provided the use of ozone in the preparation of a therapeutic system for the treatment of dental caries.
As used herein, the term xe2x80x9cozonexe2x80x9d is intended to embrace pure ozone, oxonised air and ozonised aqueous media, such as water optionally containing a reductant, such as thiocyanate or peppermint.
The ozone is delivered at a pressure sufficient to penetrate the carious tissue and at a concentration and for a period of time sufficient to kill substantially all of the micro-organisms within the carious lesion.
Preferably, a needle-sized jet of pure ozone or ozonised air in a shroud of micro-organism-free aqueous medium, e.g. water optionally containing a reductant, is injected at the desired location.
If desired, a sealant of the type known in the art may be applied to a carious lesion following ozone treatment.
The advantages of using ozone in the treatment of dental caries include the following:
1. It eliminates drilling and its attendant problems;
2. It is rapid and painless;
3. It does not require sophisticated methods of isolating the tooth;
4. No local anaesthetic is required.
The invention is illustrated in the following Examples. Unless otherwise stated, the ozone delivered in the following Examples is present in air at a concentration of 5.2%.